The elderberry is the tiny, glossy purple-black fruit of the elder, a fast-growing shrub or small tree of the genus Sambucus, borne by the hundred in broad, flat-topped clusters that nod and darken as they ripen in late summer. Each berry is barely the size of a peppercorn, with thin skin over scant juicy flesh and a few small seeds, and tastes tart, earthy and faintly musky rather than sweet. Crucially, elderberries are a cooked fruit — raw or under-ripe berries are mildly toxic — so they are simmered into syrups, cordials, jams, wine and pies, while the fragrant white elderflowers that precede them are turned into cordial and fritters.